Titlebook: Constraint Databases and Applications; ESPRIT WG CONTESSA W Gabriel Kuper,Mark Wallace Conference proceedings 1996 Springer-Verlag Berlin H

悬挂

leniency

https://doi.org/10.1007/3-540-60794-3(GIS); Abgbfrageoptimierung; Constraint Databases; Constraint Datenbanken; Constraint Processing; Constra

不足的东西

小故事

DISCO: A constraint database system with sets,talog queries and input databases with both integer gap-order [30] and set order constraints [31]. The DISCO query language can easily express many complex problems involving sets. The paper also presents efficient running times for several sample queries.

和谐

大方一点

Constraint Databases and Applications978-3-540-49456-0Series ISSN 0302-9743 Series E-ISSN 1611-3349

GULF

CRACK

Hypomania

occurrence

Ambiguity for referential integrity is undecidable,he former case rollback the operation. Since such checks are time consuming, one might consider performing them only for schemas which bear the risk of an indeterminism. This paper shows that it is . whether or not a schema may have an instance leading to ambiguities. Therefore, unnecessary checks cannot be avoided in general.